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Decimals and Roman Numerals

Date: 10/22/98 at 03:21:16
From: Richard Collecutt
Subject: Roman numerals

Do you know of any method for representing Roman numerals in a
floating point format? For example, does 10.5 = X.V?

Date: 10/22/98 at 08:26:37
From: Doctor Rick
Subject: Re: Roman numerals

Hello, Richard.

The Romans didn't have a standard way of writing fractions (or decimals.)
Usually, they just wrote out the appropriate word, such as "tres septimae"
for three-sevenths.

When they needed to do serious calculations with fractions, the Romans
used the uncia, a unit that meant 1/12 of anything.  There were names and
symbols for different multiples of the uncia.  For example, six unciae,
or 6/12, made up the semis.  The semis meant one-half, and its symbol
was an S cut in half (this looks a lot like a backward 2.)  Unfortunately,
uncia symbols didn't follow any real system, and they were never entirely
standardized.

Jeff Miller's page on the "Earliest Uses of Symbols for Fractions and

http://jeff560.tripod.com/fractions.html

It's important also to understand that Roman numerals are not a place-
value system; there is no ones place, tens place, etc., so there is
no "place" for a decimal point. If I were to invent a system for
writing fractional quantities in Roman numerals, other than writing a
fraction with Roman numerals in the numerator and denominator, I would
take a cue from the method, occasionally seen, of writing a horizontal
bar over a Roman numeral to signify multiplication by 1000:
_
M = 1000 * 1000 = 1,000,000

and use, say, a bar under a Roman numeral to signify division by 1000.

- Doctors Rick and Ursula, The Math Forum
http://mathforum.org/dr.math/

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